The benefits of fertilizer spikes for providing nutrients for trees and shrubs directly below the ground surface is known. Prior fertilizer spike injection tools, however, remain: ineffectual, time consuming and/or cost prohibitive. The prior art shall be referenced to in detail, in this regard.
The available prior art relating to the field of invention might be divided into two tool groups—standalone tools that do not require other tools to used in conjunction with their operation by the user and tools that are auxiliary to other tools required in the operation by the user. For simplicity, it may serve to refer to the former as Primary prior art tools and the latter, as Secondary prior art tools. All prior art refereed to herein, except prior art, U.S. Pat. No. 3,892,552 issued to Jacob Douglas Gay, Jr., on Jul. 1, 1975, would be classified by this definition, as Primary prior art tools. The Primary prior art tools may be further grouped by the means in which the operator applies force onto the tool in the process of injecting the fertilizer spike into the soil, such as: 1) by hand, in a pushing fashion, 2) by hand, in a ramming fashion, 3) by a single foot, in a stomping fashion or 4) by two feet, in a jumping fashion. Product differentiation between each of these categories and within each of these categories is further apparent in that, within each of these categories, options exist based on whether, and if so by what means, will: the fertilizer spike be retained within the fertilizer spike load chamber, the fertilizer spike load chamber and/or fertilizer spike retention mechanism of the tool be inserted into the soil concurrent with the insertion of the fertilizer spike and the inserted fertilizer spike load chamber and/or fertilizer spike retention mechanism be removed from the soil while leaving the fertilizer spike behind.
Numerous problems of injection and ejection exist within each of these categories. Problems associated with the prior art where the fertilizer spike load chamber and/or fertilizer spike retention mechanism is injected into the soil concurrent with the injection of the fertilizer spike include: extraneous operator time, energy and effort required in the injection and ejection processes from overcoming the added friction from injecting extraneous mass such as the fertilizer spike load chamber and/or the fertilizer spike retention mechanism in conjunction with the fertilizer spike, from the soil adhering to the perimeter of the extraneous mass and from clogging and jamming of the fertilizer spike load chamber and/or the fertilizer spike retention mechanism with soil forced between the fertilizer spike and the walls of the fertilizer spike chamber and/or the fertilizer retention mechanism thereby failing to inject or eject the fertilizer spike, requiring maintenance prior to it's next use and causing a decreased range of soil firmness condition applications; difficult, complex, awkward or supplemental procedures and/or special expertise to inject the fertilizer spike into the soil; difficult, complex, awkward or supplemental procedures and/or special expertise and/or the requirement of auxiliary attachments to remove the tool from the soil after injecting the fertilizer spike while leaving the fertilizer spike behind; maintenance of the tool after removing the tool from the soil from soil adherence and exposure to corrosion form soil contamination.
Problems associated with the prior art category where there is excessive step-up height include: ineffectual operation, extraneous effort as well as awkward or unsafe operation from unstable and off-balance operation.
Problems associated with the prior art category where there is no fertilizer spike retention mechanism include: awkward/uncomfortable bending or kneeling to insert the fertilizer spike into the tool or into the ground.
Problems associated with the prior art category where there is no driver rod retention mechanism include: inadvertent displacement of the fertilizer spike prior to injection resulting in time-consuming as well as the need of bending or kneeling to insert the fertilizer spike into the tool resulting in awkward/uncomfortable/time-consuming operation.
Problems associated with the prior art category where there is hand/arm/shoulder movement to push the fertilizer spike into the soil include: extraneous operator time, energy and effort required in the injection process from a restriction to upper body strength resulting in deriving a limited amount of operator force and limiting the range of application due to soil firmness conditions.
Problems associated with the prior art category where there is hand/arm/shoulder movement to repeatedly ram the fertilizer spike into the soil include: excessive cost from damaged fertilizer spikes, extraneous operator time, energy and effort required in the injection process from clogging and jamming of the fertilizer spike load chamber, the fertilizer spike retention mechanism and/or the driver rod head with the end of a broken fertilizer spike, from ongoing replacement and maintenance of the striker pad and the rubber cushion, from partial absorption of the operator's force by the cushioned striker pad and from having to raise and lower a weighted striker rod thereby resulting in: failure to inject or eject the fertilizer spike, limited range of application due to soil firmness conditions and a diminished return of operator effort being derived.
Problems associated with the prior art category that is limited to single-foot pedal include: extraneous operator time, energy and effort required in the injection process from off-balance/off-center operation thereby resulting in deriving a limited amount of operator force and limiting the range of application due to soil firmness conditions as well as awkward or unsafe operation.
Problems associated with the prior art category that is limited to single-foot pedal with reciprocal movement include: extraneous operator time, energy and effort required in the injection process from off-balance/off-center operation thereby resulting in deriving a limited amount of operator force and limiting the range of application due to soil firmness conditions as well as awkward or unsafe operation in addition to extraneous operator energy from the binding resistance of off-centre pedal operation of the sliding foot pedal mechanism to the wall of the structure that contains it resulting in further reduction in the amount of operator force derived, further limiting of the range of application due to soil firmness conditions as well as increased awkward or unsafe operation.
Problems associated with the prior art category where the foot pedal is biased to a retracted position with a coil spring include: extraneous operator time, energy and effort is required during operation to counter the continual resistance of the coil spring resulting in a diminished return of operator effort being derived thereby limiting the range of application due to soil firmness conditions; time consuming, unstable/off-balance/operator jolting/unsafe operation from the disconnection of the driver head of the tool with the contact surface of the fertilizer spike at the time the fertilizer spike/pellet is inserted into this prior art to the moment of contact with the head of the driver rod and because of the step-ledge returning to the original step-on height should the operator step-off the tool before injection has been completed, as is most often the case, resulting in jolting of the operator, unstable and off-balance operation, loss of the visual depth of the injection obtained, a diminished return of operator effort being derived as well as possible clogging and jamming of the fertilizer spike load chamber, the fertilizer spike retention mechanism and/or the driver rod head with the end of a broken fertilizer spike from the ramming effect. There is also the added the cost of the coil spring itself as well.
Problems associated with the prior art where a plastic cap is used as an auxiliary tool in the injection process include: awkward/uncomfortable/timely bending or kneeling to insert the fertilizer spike into the ground; digging out the plastic cap prior art from the soil prior to it's next use; hitting one's fingers with a hammer while steadying the fertilizer spike; requiring other tools in the injection and ejection process which need to be maintained and which can be misplaced in the process.
Problems associated with the prior art without the inability to have simultaneous injection of the fertilizer spike into the soil with the ejection of the fertilizer spike from the fertilizer spike load chamber and the fertilizer spike retention mechanism include: extraneous operator time, energy and effort required in the injection and ejection processes.